This invention relates to a method of manufacturing a magnetic strip into a speed ring. More specifically and without limitation, this invention relates to a continuous process using computers and microprocessors to manufacture speed rings.
A speed ring is a strip of magnetic material that is formed into a ring that can be calibrated to take readings of how fast a device is rotating. For example, a speed ring can be used to determine the speed and the direction of rotation of a rotating plate such as used in a hydraulic pump or motor. The speed ring is able to determine the speed of a rotating device by using a Hall Effect sensor that senses the number of pairs of magnetic poles (a North pole and a South pole) on the speed ring and sends this information to a microprocessor.
As the diameter of the speed ring changes, its circumference also changes as does the spacing and number of magnetic poles. Consequently, to produce multiple circumference speed rings, the length of the magnetic strip, the spacing of the pairs of poles, and the number of pole pairs must be accurately controlled.
The ability to accurately control the pole pairs becomes especially difficult when the magnetic strip needs to be formed into a circular shape of a fixed circumference. The problem is compounded by the need to make several different diameter circles. The prior art describes a way of using a fixed pole spacing magnetizing feature to create magnetized strips of material that are of varying lengths and have a whole number of pole pairs. Then, the ends of the strips are butted together in a circular ring. Creating a speed ring using this method based on the length of the magnetic material causes discontinuities in the speed ring because the ring is created using the fixed geometry of the magnetic strip.
Thus, it is a primary object of the present invention to provide a method of manufacturing a speed ring that improves upon the state of the art.
Another object of the present invention is to provide a method of manufacturing a speed ring by using microprocessors and computers.
Yet another object of the present invention is to eliminate excess machining and extra work in the process of forming a speed ring.
A further object of the present invention is to use a method of manufacturing a speed ring that determines the length of the ring by using magnetic flux instead of strip size to ensure better accuracies.
These and other objects, features, or advantages of the present invention will become apparent from the specification and claims.